To Babysit a Demon
by exocara
Summary: [GEN. No pairings.] Chrome asks Tsuna to babysit her cousin, Mukuro. Tsuna accepts, but no amount of preparation would ready him for the most hellish babysitting experience of his entire life.


**_Anonymous asked: au where mukuro is a bratty child and tsuna is his beleagured babysitter_.**

 **this is basically just 1k+ of Tsuna's suffering. I'm sorry, Tsuna.**

 **also, less of bratty child and more of demon that crawled straight out from hell**

* * *

If Chrome hadn't been one of Tsuna's close friends, he probably wouldn't have taken up the job. However, he had known Chrome since they were fifteen, _and_ he was pretty short on money. Chrome was paying him _twenty dollars an hour_ to babysit her cousin and he couldn't just pass up money like that.

(Except, he could. He had heard _so many stories_ about that creepy Mukuro kid from Chrome – of course, not in those exact words – and how he had chased out all the babysitters who had worked with him. He even made a good chunk of the cry.

But then, Chrome gave him the puppy eyes and also nonchalantly brought up all the times she had babysitted for him with I-Pin, Lambo, and Fuuta. Tsuna couldn't say no anymore, not if he wanted his conscience to like him.)

And so he was here, feeling like he had just sold his soul to the devil. Chrome had told him the basics, like Mukuro's bedtimes, what he could and could not eat, what he _would_ and _would not_ eat… stuff like that.

It probably wouldn't be that bad… right? It was only six days…

-o-

 **Day One: The Realm of Hell (Illusions)**

The first day was alright. Mukuro behaved like an innocent, wonderful child. Tsuna was still on guard, though, because he knew. Ohhh, he _knew_. He knew that the little shit was just trying to lull him into a false sense of security so that the bad behavior he was going to pull would take _double effect_ and be 'super effective! Babysitter fainted.'

But Tsuna wasn't going to fall for it. Not that Mukuro knew; Tsuna treated him with civilly, with a smile on his face and what seemed like eternal cheer. He was good at that; living with a hell tutor named Reborn did that to you. Not to mention, he always had to treat his father nicely whenever the idiot decided to grace them with his presence or his mother would be sad. So, yeah. Tsuna was good at pretending to be nice and unflappable.

The day was coming to a close and Tsuna was tucking Mukuro into bed. Mukuro was half-heartedly putting up a fight, whining about how he wasn't even tired, so why should he go to bed anyway?

"Because it is late, and good children should rest," Tsuna replied. If he hadn't been watching closely, he wouldn't have seen the _evil_ glint in Mukuro's eyes as the boy pointed to his semi-opened closet.

"What about that child?" he asked. Tsuna felt a chill go up his spine.

"Well, that child isn't a good child, then!" he said, smile frozen in place on his face. He wasn't going to give in, dammit! He wasn't going to let himself get bothered by Mukuro's obviously fake words!

…

Tsuna didn't sleep well that night.

-o-

 **Day Two: The Realm of Hungry Ghosts (Imitation)**

 _It had begun._

Tsuna was helping Mukuro with his 'art project'. He didn't really know what Mukuro was trying to do, and his mind kind of blanked out the third time Mukuro talked about evil humans and murder, but he knew that Mukuro was using an awful lot of red and indigo.

' _Splash!_ '

Ah, and now Tsuna was entirely drenched in indigo paint! Wonderful! Simply wonderful!

"Mukuro, that isn't very nice of you," Tsuna said. Fortunately, he was able to restrain his anger.

"Tsunayoshi, that isn't very nice of you," Mukuro repeated mockingly.

"…"

"…"

"Um, Mukuro, let's go clean up, shall we?"

"Kufufu, Tsunayoshi, let's go clean up, shall we?"

 _If you give in now, if you yell at him, he'll win. Are you seriously going to lose to this disgusting child?_

Tsuna was beginning to understand why Hana hated children.

-o-

 **Day Three: The Realm of Beasts (Animal Summoning)**

Tsuna woke up this morning to find snakes in his bed.

Good start.

He got out of bed and stepped on something furry. He looked down to see a dead rat.

"…"

Resisting the urge to let out his signature shriek – _if you do that, he'll win_ – Tsuna took a deep breath to swallow his horror at the entire situation and plastered a cheery smile on his face. He got a plastic bag from the kitchen downstairs to clean up the room.

When he had done so, he opened the back door of the house, which led to the bin outside, and a bucket of insects fell onto him.

"…"

Only the sight of Mukuro in the distance, staring at him intensely, trying to see if Tsuna had any reaction, kept Tsuna from breaking down right there and then.

 _If you give in now, he'll win. He cannot win._

-o-

 **Day Four: The Realm of Demons (Combat)**

"Mukuro, put down that knife."

"Kufufu, and why should I, Tsunayoshi?"

Tsuna was _this close_ to just punching Mukuro in the face. But he didn't. Because he didn't want Mukuro to win.

"Because I don't want you to get hurt," Tsuna said patiently. Something flickered in Mukuro's eyes and he slowly set down the knife. Tsuna took it and placed it somewhere high up. He was pretty sure that Mukuro was still able to access it, but it was the symbolism that counted.

After making sure that every knife was more or less Mukuro-proofed, Tsuna turned back to Mukuro to ask a question. He didn't remember what the question was because, at that moment, Mukuro stabbed him in the thigh with a fork.

-o-

 **Day Five: The Realm of Humans (Battle Aura?)**

[ _INFORMATION REDACTED_ ] and then Mukuro [ _REDACTED_ ]

[ _PRIVATE_ ] and Tsuna didn't want Mukuro to win, so he didn't [ _REDACTED_ ]

In the end, [ _CENSORED_ ] lotus roots [ _REDACTED_ ] but there were lotus vines everywhere.

[ _REDACTED_ ] [ _REDACTED_ ] [ _REDACTED_ ]

[ _REDACTED_ ] [ _REDACTED_ ] [ _REDACTED_ ]

[ _REDACTED_ ] [ _REDACTED_ ] [ _REDACTED_ ]

Tsuna cried himself to sleep that night.

-o-

 **Day Six: The Realm of Heavens (Possession)**

When Tsuna opened his eyes, he couldn't see anything. There was something in his mouth, so he couldn't open it. It tasted of cloth, so Tsuna assumed that he had been blindfolded and gagged by the hellspawn named Mukuro.

He tried to move his arms and legs but he couldn't. So: tied up, blindfolded, and gagged. That was great.

"You know, Tsunayoshi," Tsuna heard Mukuro's voice coming from right beside him. "You are my favorite babysitter. I didn't really think I was going to like you at first, but I was proven wrong. I _really_ do like you, Tsunayoshi."

Tsuna _really_ didn't like Mukuro's tone of voice. But he couldn't give in, or he wouldn't win.

"So, I'm going to put you in a jar so I can keep you and see you forever." Tsuna felt something pat his head, and then the cool press of sharp metal against his skin.

…

 _Fuck_ winning.

Chrome burst into the room that very moment and carried Mukuro away.

-o-

Apparently, Mukuro hadn't been joking when he said that Tsuna was his favorite babysitter. After that hellish experience, Chrome would tell Tsuna that Mukuro wanted Tsuna to go over and babysit him again.

Tsuna refused every time. Chrome, bless her, didn't press him.


End file.
